//
// CATGL - Cheap Action-game Tool with WebGL.
//
// Copyright 2010, tmasda.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

function hermite(t, startpos, startvec, endpos, endvec){
    var t2 = t * t;
    var t3 = t2 * t;
    var p0 = 2*t3 - 3*t2 + 1;
    var v0 = t3 - 2*t2 + t;
    var p1 = -2*t3 + 3*t2;
    var v1 = t3 - t2;
    
    var x = startpos[0]*p0 + startvec[0]*v0 + endpos[0]*p1 + endvec[0]*v1;
    var y = startpos[1]*p0 + startvec[1]*v0 + endpos[1]*p1 + endvec[1]*v1;
    var z = startpos[2]*p0 + startvec[2]*v0 + endpos[2]*p1 + endvec[2]*v1;
    return new Float32Array([x, y, z]);
}
